Automatic swimming pool cleaners of the type that move about the underwater surfaces of a swimming pool are driven by many different kinds of systems. A variety of different pool-cleaner devices in one way or another harness the flow of water, as it is drawn or pushed through the pool cleaner by the pumping action of a remote pump for debris collection purposes.
Suction automatic pool cleaners are very successful when there is fine debris or debris that become soft in water. This fine debris is sucked up by the cleaner and deposited into a pump basket, or other debris-collection device, and the really fine debris passes into the pool filter. An example of a suction cleaner is disclosed in commonly-owned U.S. Pat. No. 6,854,148 (Rief et al.), entire contents of which are incorporated herein by reference.
Suction automatic swimming pool cleaners are used in places with much sand and slit. Although suction cleaners can take leafy debris once it has softened in the pool, large debris such and large acorns and hard leafs would plug up a suction cleaner. Suction swimming pool cleaners are also limited to the debris size due to loss of suction if the inlet and/or outlet orifices are widened to accommodate such large debris and the possibility of large debris clogging the pool pipes.
Conversely, pressure automatic swimming pool cleaners are very successful when there is large debris such as leaves and acorns, these large debris are pulled off the pool surface by virtue of a venturi effect and are placed into a debris-collection device, such as a bag, above the cleaner. An example of a pressure cleaner is disclosed in commonly-owned U.S. Pat. No. 6,782,578 (Rief et al.), entire contents of which are incorporated herein by reference. With a pressure swimming pool cleaner, the limitation is the opposite to the suction cleaner. In removing very large debris from the swimming pool, a pressure cleaner uses a collection bag or other receptacle. Regardless of how fine the walls of such receptacle are, sand and slit can pass through the them back into the pool.
The problem is that most often only one cleaner is used in a pool. Therefore, people have either a suction cleaner or a pressure cleaner. Many swimming-pool builders place a suction cleaner into a pool when it is built. This is because there is no real landscaping around the pool at the time of the cleaner installation. However, just few years later, when trees and bushes have grown up, the debris becomes overwhelming and constantly plugs the suction cleaner.
Still with the pressure cleaner, no matter how large debris is in the pool, there is always sand and slit from cement and other elements of the surrounding environment. Such fine debris will pass through the debris-collection bag back into the pool. Although some swimming pool pressure cleaners have tails that supposedly whip the debris toward the main drain, in reality such tails only bring the dirt into suspension until it falls back on the pool bottom to start the process all over again. Attempts have been made to utilize both a suction power and a pressure flow from remote pumps by the same swimming pool cleaner apparatus. One such apparatus is disclosed in U.S. Pat. No. 5,099,535 (Chauvier et al.). The apparatus of the Chauvier et al. patent is connected to both a pressure and suction remote pumps at the same time. However, only the suction hose is used for removal of the debris from the swimming pool underwater surface. The Chauvier et al. cleaner utilizes the pressure flow only for displacement of the cleaner along the underwater pool surface such that the Chauvier et al. cleaner remains a suction cleaner at all times and retains disadvantages of suction cleaners described earlier. Therefore, to remove large or hard debris from the swimming pool, one would have to use a separate cleaner or cleaning method which accommodates successful removal of such large debris. It should further be noted that, because suction and pressure line connectors are not in the same vicinity of a swimming pool, the connection to both lines at the same, as proposed by the Chauvier et al. patent, is practically not possible.
U.S. Pat. No. 7,168,120 (Habif et al.) discloses a pressure-fed vacuum swimming pool cleaning robot. The robot of the Habif et al. patent has a structure which extends from a debris-inlet end applied to the swimming-pool underwater surface to an opposite debris-outlet end which is distal from the underwater surface. In the robot of the Habif et al. patent, the suction is always created at the debris-outlet end by either a connection of the debris-outlet end to a suction hose or by creating a venturi effect at the debris-outlet. The structure of the Habif et al. patent consistently operates as a suction cleaner which successfully removes only fine or very soft debris. This structure is not configured for removal of large and hard debris which would plug up the debris inlet as well as inner passages of the Habif et al. robot. Therefore, as with the Chauvier et al. patent, large or hard debris would have to be removed from the swimming pool by a separate cleaner different from the robot of the Habif et al. patent or by some other means designed for removal of such large debris.
Also, in some states law requires variable speed pumps. It would be beneficial to have a cleaner which consistently provides an efficient performance with pumps running at lower or higher rates and is successful in removing both fine and large debris from the swimming-pool underwater surface.
It would be desirable to have a pool cleaner allowing manufacturing to be standardized and the end user have easy accessability to the cleaner parts for maintenance.